<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        #app {
            margin: 0 auto;
            height: 200px;
            width: 200px;
            border: 1px solid #000000;
            position: relative;
            transition: all 1s;
            /* transform-origin旋转中心：x-默认值50% y-默认值50% */
            /* transform-origin: 0 0;  */
            transform-origin: right top; 
        }
        #app:hover {
            transform: rotate(225deg);
        }

        
        .father {
            margin: 0 auto;
            width: 300px;
            height: 300px;
            background-color: #FFFFFF;
            display: flex;
            overflow: hidden;
            font-size: 13px;
            color: #ffffff;
            border-radius: 20%;
        }
        .father:hover .child_a {
            font-size: 16px;
            transform: rotate(0deg);
        }
        .father:hover .child_b {
            font-size: 18px;
            transform: translateY(0)
            
        }
        .father:hover .child_c {
            font-size: 16px;
            transform: rotate(0deg);
        }
        .child_a {
            width: 100px;
            height: 300px;
            background-color: deeppink;
            transform-origin: left bottom;
            transform: rotate(-90deg);
            transition: transform 0.3s, font-size 1.5s;
            display: flex;
            align-items: center;
            justify-content: center;
        }
        .child_b {
            width: 100px;
            height: 300px;
            white-space: nowrap;
            background-color: deepskyblue;
            transform: translateY(100%);
            transition: transform 0.3s, font-size 1.5s;
            display: flex;
            align-items: center;
            justify-content: center;
        }
        .child_c {
            width: 100px;
            height: 300px;
            background-color: green;
            transform-origin: right bottom;
            transform: rotate(90deg);
            transition: transform 0.3s, font-size 1.5s;
            display: flex;
            align-items: center;
            justify-content: center;
        }
    </style>
</head>
<body>
    <!-- <div id="app"></div> -->

    <div class="father">
        <div class="child_a">HELLO CSS</div>
        <div class="child_b">HELLO VUE</div>
        <div class="child_c">HELLO JS</div>
    </div>
</body>
</html>